At a glance
Key points
- Apply the hierarchy in order and justify departures from fixed guarding.
- Assess foreseeable access during production, setup, clearing, cleaning and maintenance.
- Guard openings must account for reach and safety distance.
- Interlocked guards and protective devices depend on reliable stopping and restart control.
- Training does not replace practicable physical protection.
1. The Regulation 11 hierarchy
The hierarchy is deliberately practical. Where a dangerous part can be fully enclosed with a fixed guard and routine access is not needed, that is normally the starting point. When access is required, movable guards, interlocks, guard locking or protective devices may be appropriate. Protection appliances and safe systems support—but do not casually replace—engineering controls.
| Level | Typical examples | Key question |
|---|---|---|
| 1. Fixed guards | Bolted or retained covers, mesh panels, tunnel guards | Can access be prevented without creating unreasonable operational problems? |
| 2. Other guards or devices | Interlocked doors, guard locking, light curtains, scanners | Will the dangerous movement stop before access, and is restart controlled? |
| 3. Protection appliances | Jigs, holders, push-sticks, handling aids | Do they keep the person clear during a defined task? |
| 4. Information and training | Instructions, signs, procedures, supervision | What residual risk remains after practicable physical measures? |
2. What counts as a dangerous part?
Dangerous parts include more than exposed blades. Rotating shafts, chucks, nip points, belts, gears, moving slides, crushing zones, robot movement, stored energy, hot tools and ejected material can all create machinery risk. The assessment should consider the complete movement and foreseeable human approach.
Connected machines can create new danger zones at conveyor transfers, pallet openings and interfaces. A component may be guarded individually but still allow access through the line.
3. Suitability requirements for guards and protective devices
Regulation 11 also sets characteristics expected of guards and devices. They should be suitable for purpose, of good construction, maintained in an efficient state and working order, and not increase overall risk. They should not be easily bypassed or disabled, should be far enough from the danger zone, and should not unnecessarily restrict the view of the operating cycle where that view is needed.
Guarding should enable essential fitting, replacement or maintenance work where possible while restricting access to the area in which that work must be done. This is why task-led design is important: a technically strong panel in the wrong place can drive repeated removal.
4. Fixed, interlocked or guard locked?
Choose based on access frequency and stopping behaviour. A fixed guard suits infrequent access where removal can be controlled. An interlocked guard initiates a stop when opened. Guard locking retains the guard closed until the risk has reduced sufficiently, which may be necessary where run-down, pressure, heat or other hazards persist.
A light curtain or scanner can preserve open access, but only where the protective distance, approach, reach-around, reset and machine response are suitable. Presence sensing does not provide physical containment.
5. Inspection and maintenance
A guard that was suitable at installation can become ineffective through damage, missing fasteners, door sag, misalignment, bypass, altered openings or changes to the process. Define inspection frequency based on use and risk, and give operators a simple route to report damage.
After modification, verify that access, stopping and restart behaviour still meet the safety requirements. Keep a record of findings and repairs.
Sources and review basis
Authoritative references
This guide summarises general engineering considerations. Current legislation, guidance and standard editions should be confirmed for the specific project.
How Oxford Machine Guarding can help
We can survey the equipment, define the mechanical guarding and safety-system scope, develop the design, supply and install the solution, and provide testing and handover records appropriate to the agreed project boundary.
Important: this guide provides general technical information. It is not a substitute for a machine-specific risk assessment, legal advice, or verification by the responsible dutyholder.
